Electric energy meter and electricity larceny prevention circuit thereof

Abstract

The invention belongs to the field of power electronic measurement and provides an electric energy meter and an electricity larceny prevention circuit of the electric energy meter. A power terminal adopts a filter unit and a wave-form adjustment. The electricity larceny prevention circuit of the electric energy meter comprises a microprocessor and a current transformer, wherein the microprocessor is matched with the current transformer. When alternating current of the secondary side of the current transformer is in a zero-crossing current region of the secondary side of the current transformer, frequency changes of a rectangular impulse wave output through the secondary side of the current transformer are detected, connection states of the secondary side of the current transformer are accurately adjusted and the purpose of omni-directional monitoring of behaviors of electricity larceny is achieved, and therefore the problems that the connection states of the secondary side of the current transformer can not be accurately detected in the prior technology of electricity larceny are solved.

Description

Technical field [0001] The invention belongs to the field of power electronic metering, and in particular relates to an electric energy meter and an anti-theft circuit. Background technique [0002] At present, in the power system, stealing electricity by short-circuiting the secondary side of the current transformer in the power terminal is a common method of stealing electricity. [0003] In order to be able to detect power theft behavior, the existing anti-theft technology is to add a coupling coil at the current transformer, and use the coupling coil to detect the change of the inductance of the secondary circuit of the current transformer, and pass the change of the inductance. Judge the connection status of the secondary side of the current transformer, so as to know whether the stealing behavior occurs. However, in the above anti-theft technology, the magnetic permeability of the magnetic medium in the coupling coil will change with the change of the current under the actio...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide an electric energy meter anti-stealing circuit, which aims to solve the problem that the existing anti-stealing technology cannot accurately detect the connection state of the secondary side of the current transformer

Images